Comment 85 for bug 1011792

I've been having similar lockups on dom0's running Ubuntu 12.04 LTS w/kernel linux-image-3.2.0-32-generic as a dom0. Below is output from the last one, which shows the same stack trace being seen in the virtual kernel image. I took the pgslam/setup_hi1_4xlarge_for_crash_test.sh test scripts and modified the setup to not setup md0 and am just using my local storage instead. On 3.2.0-32-generic, the system locked up repeatedly when pgslam was run. I then updated the kernel to 3.2.0-39-generic found on precise-proposed and re-tested without any issues. I wanted to report my findings here since I haven't seen anyone confirm the fix for precise. Not sure if I can do that based on my findings, but would be happy to if possible to help move the fix along to precise-updates.

[70987.896664] BUG: soft lockup - CPU#1 stuck for 22s! [swapper/1:0]
[70987.896822] Stack:
[70987.896857] Call Trace:
[70987.896880] <IRQ>
[70987.897138] <EOI>
[70987.897185] Code: cc 51 41 53 b8 1c 00 00 00 0f 05 41 5b 59 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 51 41 53 b8 1d 00 00 00 0f 05 <41> 5b 59 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc
[71015.896695] BUG: soft lockup - CPU#1 stuck for 22s! [swapper/1:0]
[71015.896940] Stack:
[71015.896985] Call Trace:
[71015.897012] <IRQ>
[71015.897420] <EOI>
[71015.897487] Code: cc 51 41 53 b8 1c 00 00 00 0f 05 41 5b 59 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 51 41 53 b8 1d 00 00 00 0f 05 <41> 5b 59 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc
[71043.464982] igb 0000:01:00.0: eth0: Reset adapter
[71043.896750] BUG: soft lockup - CPU#1 stuck for 22s! [swapper/1:0]
[71043.896981] Stack:
[71043.897026] Call Trace:
[71043.897053] <IRQ>
[71043.897443] <EOI>
[71043.897507] Code: cc 51 41 53 b8 1c 00 00 00 0f 05 41 5b 59 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 51 41 53 b8 1d 00 00 00 0f 05 <41> 5b 59 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc
[71048.180847] INFO: task kworker/u:2:19718 blocked for more than 120 seconds.
[71048.180893] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[71071.896790] BUG: soft lockup - CPU#1 stuck for 22s! [swapper/1:0]
[71071.897023] Stack:
[71071.897068] Call Trace:
[71071.897095] <IRQ>
[71071.897491] <EOI>
[71071.897555] Code: cc 51 41 53 b8 1c 00 00 00 0f 05 41 5b 59 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 51 41 53 b8 1d 00 00 00 0f 05 <41> 5b 59 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc
[71088.072808] INFO: rcu_sched detected stalls on CPUs/tasks: { 4} (detected by 3, t=60034 jiffies)